In recent years, a method of forming a pattern having a size less than exposure resolution limit of lithography is required in accordance with miniaturization of semiconductor devices.
As one of such methods, a fine pattern formation method is known which includes forming a base film on a substrate, forming a first resist pattern on the base film, irradiating vacuum ultraviolet rays on the first resist pattern, forming a second resist pattern on the base film, etching the base film using the first and second resist patterns as a mask, and removing the first and second resist patterns. This method, for example, is disclosed in JP-A 2005-197349.
By using the fine pattern formation method, it is possible to improve various resistances such as etching resistance using a cure effect by the vacuum ultraviolet rays, and to form a sparse pattern in which deformation or “falling” is suppressed.